A switch-capacitor network is a commonly used circuit for discrete time signal processing, which includes a plurality of switches and a plurality of capacitors. By turning on/off these switches, a user may control charge storage status of these capacitors, so as to process an input signal.
The switch-capacitor network is commonly used in a filter technique. Compared to a capacitor-resistor analog filter circuit, a filtering effect of the switch-capacitor network is mainly determined by size ratios of areas of the capacitors therein. Even if the areas of the capacitors are changed due to a fabrication process variation, since the size ratios of the capacitors are not changed along with the fabrication process variation, the filtering effect of the switch-capacitor network is unchanged. Therefore, the switch-capacitor networks are suitable for being fabricated within chips.